The present invention relates to an apparatus for driving camshafts in an internal combustion engine of a vehicle such as a motorcycle.
In a typical example of a conventional camshaft driving apparatus, gears rotatably supported by respective camshafts provided at an upper portion of an engine body and a gear rotatably supported by a crankshaft provided at a lower portion of the engine body are cooperatively connected through a gear train including at least two intermediate gears which are engaged to each other so as to drive the camshafts from the crankshaft through the gear train. Such an arrangement is disclosed in Japanese Laid-Open Patent Application No. 59346/81.
In such a conventional camshaft driving apparatus, the intermediate gears are mounted in the engine body by fixedly mounting respective shafts for rotatably supporting the associated intermediate gears to the engine body after assembling the intermediate gears on the respective shafts, which is a complicated assembly operation.